The Colombian ambassador to Bern, Claudia Jiménez, made the announcement on Thursday in the Swiss capital after officially informing Foreign Minister Micheline Calmy-Rey.The decision comes a week after the Colombian government engineered the successful release of 15 hostages including Ingrid Betancourt, a former presidential candidate in that country.Colombia has also said it expects a response from Switzerland into the dealings of a Swiss mediator, Jean-Pierre Gontard, who was involved in negotiations with Farc.Documents suggesting Gontard had a cosy relationship with Farc leaders were discovered on a seized computer belonging to Raul Reyes, a senior member of the group killed in March in a military operation launched by the Colombian government.Jiménez said Bogotá would wait for the Swiss to move before taking action on the issue.